Invasive Non-Native Species (INNS)

The three invasive plants that pose the greatest threat within the Eden catchment currently are Himalayan balsam, Japanese knotweed and giant hogweed. All three species have potential to negatively impact on biodiversity as they outcompete our native plants. As the River Eden has more species of plants associated with it than any other river in the UK it is important that we deal with this threat. These invasive plants also leave river banks exposed when they die back in winter which can lead to significant erosion and sedimentation. This increase in sediment can then negatively impact some of the protected species that inhabit the river including white-clawed crayfish and Atlantic salmon. Other negative impacts associated with these species include structural damage caused by Japanese knotweed growing through tarmac, mortar and drains, and, severe burns to human skin resulting from contact with giant hogweed sap.

Other invasive species of concern include American signal crayfish and a parasite of fish called Gyrodactylus salaris. Neither of these are currently found in the Eden catchment but could arrive at any time and be disastrous for the local environment and economy.

The Eden catchment is one of the last strongholds of the native white-clawed crayfish. There continued existence is threatened by signal crayfish which have wiped out entire populations, elsewhere in the UK, by outcompeting them for resources and also through the fungal infection, crayfish plague, which they carry. Signal crayfish have not only already colonised rivers in all surrounding counties but also the Derwent catchment in West Cumbria.
Local fish populations are at risk from the invasive freshwater parasite called Gyrodactylus salaris, which is found in Scandinavia and other parts of Europe. It causes a serious fish disease called Gyrodactylosis which infects the skin, gills and fins of salmon, trout and some other species of freshwater fish. This disease is one of the biggest threats to the wild salmon population in the UK and has the potential to cause widespread losses in the UK’s valuable stocks of both wild and farmed freshwater Atlantic salmon. If introduced here it would be difficult to eradicate because of the very diverse nature of our river ecosystems. For more information click here.

Biosecurity

Throughout the UK and abroad there are many invasive species, including Gyrodactylus salaris and the spores of crayfish plague, that would have huge negative impacts should they be introduced into the Eden catchment. In order to prevent this from happening it is essential that appropriate actions are taken by everyone concerned - this is often referred to as biosecurity. This is particularly important for equipment such as boats, fishing nets and waders etc. that have been used outside of the Eden catchment. Appropriate biosecurity is relatively simple to achieve by following the Check, Clean, Dry mantra (Download the poster here). It is however essential that equipment is completely dried out, which in the case of felt sole waders is virtually impossible. If equipment can not be dried then it should be disinfected for a prolonged period to kill any fungal spores.

Eden Invasive Species Group (EISG)

In 2010 a partnership between Eden Rivers Trust and Natural England brought together organisations, landowners and other stakeholders either already involved in, or interested in, the control of INNS. This resulted in the formation of the group which, now supported by the Environment Agency, coordinates efforts to survey, map and prioritise control of the already existing invasive, non-native species. The group is also endeavouring to prevent the spread of existing or introduction of new invasive species by  raising awareness of the issues involved. The group was coordinated by Alison Reed in 2011, and, is now coordinated by Paul Greaves .

2011 control season

In 2011 five demonstration sites were set up at Ullswater, Lazonby, Armathwaite, Carlisle and Dalston to trial different techniques for Himalayan balsam control. During the course of the season an amazing 146 volunteers attended 46 organised events to remove Himalayan balsam from these sites resulting in 12km of bank being controlled. The preliminary results from the trial suggest that a combination of spraying with herbicide, strimming and hand pulling are most effective. It is important to revisit sites towards the end of the season to remove late germinating plants.
In July a fantastic event was organised in conjunction with Ullswater Steamers and their mascot, Sammy the Squirrel, on the shores of the lake. It was attended by 47 people who worked hard all day pulling up Himalayan balsam. They were rewarded with a free boat trip on the lake provided by Ullswater Steamers!
The event was aimed at involving local people and land owners, as well as visitors to the area, in the initiative. It was also aimed at raising awareness of the problem and particularly the “Check clean dry” campaign to prevent the spread of invasive non-native species from one water body to another.
It has been fantastic how all these different organisations and land owners have come together and achieved so much, with enormous help from volunteers. Working together we will have a far greater effect than any of us working in isolation.

2012 control season

The Eden Invasive Species Steering Group were in agreement that work should be continued at the demonstration sites in 2012. It was also agreed that work should be expanded into the headwaters where maximum impact can be achieved. As seeds are dispersed downstream it is essential that control work starts at the furthest upstream extent and works down. The plan for 2012 is to target control work around headwater streams in the Ullswater area, and, to work downstream from Kirkby Stephen, which is the furthest known upstream point where Himalayan balsam can be found.
Japanese knotweed is found in small patches throughout the Eden catchment. We are proposing to carry out control work in some of the known sites, as unchecked, this species will become a much greater problem. Treatment with chemical herbicide is the most effective technique for treating Japanese knotweed and we are in the process of acquiring stem injection kits which will enable best application. These kits will also enable treatment of giant hogweed in areas the Environment Agency are unable to treat.

Eden Rivers Trust is also working with the county-wide coordinator of the Cumbria Freshwater Invasive Non-native Species (FINNS)

Tell us where there are invasive species in the Eden Valley - You can do this by going to http://www.scrt.co.uk/ and using the on-line recording form by clicking on 'invasive species in Cumbria' / 'record an invasive species'. Records of Japanese knotweed and giant hogweed can be reported directly to Paul Greaves This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

We want your help to control non-native species in the catchment by:

•  Helping us survey the river for invasive species throughout the summer •  Getting involved with controlling non-native invasive species at our demonstration sites and other areas
•  Controlling  invasive species on your stretch of the river
•  Forming or joining a local group to carry out control methods in your area